Abstract
Purpose: Our goal was to develop two-tier strategy based on in house-designed methylation specific-duplex polymerase chain reactions (MS-PCRs) that could serve as a relatively simple, cost effective, time efficient approach for molecular screening of imprinted regions on chromosomes 15 and 14.
Patients and methods: Patients were referred to examination during infancy due to hypotonia and motor development delay. Duplex MS-PCRs were performed that enabled detection of methylated/unmethylated DNA in NDN and MEG3 CpG islands via plurality of detection channels on PCR instrument Rotor Gene 6000.
Results and discussion: Both, copy number variations as well as methylation changes, were revealed by our in house-designed methodology by focusing NDN gene. No imprinting aberrations were yet discovered in MEG3 gene. Clinical features of the patients were compared. In agree with literature no typical facial features were observed in PWS patient with imprinting defect and AS UPD patient seems to have a relatively better development and language ability in comparison to deletional form of the disease.
Conclusion: In conclusion we were able to establish new, throughput and robust diagnostic approach to PWS/AS.
Angelman syndrome
differentially methylated region
maternally expressed 3 (non-protein coding) aliases GTL2
methylation-specific polymerase chain reaction
necdin, melanoma antigen (MAGE) family member
Prader Willi syndrome
uniparental disomy
maternal uniparental disomy for chromosome 14
paternal uniparental disomy for chromosome 14
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